The Sun is about four and a half billion years old, so it’s been around awhile. Compared to some of the galaxy’s oldest stars, though, it’s a youngster. Some stars have been around since shortly after the universe was born.
In the Milky Way Galaxy, many of those ancient stars reside in globular clusters — giant balls of stars that may have formed as the Milky Way itself was taking shape.
An example is Messier 5. It’s in the southeast at nightfall, in the constellation Serpens. It’s a bit too faint to see with the eye alone, but through binoculars it looks like a fuzzy star.
M5 is about 25,000 light-years away. It contains several hundred thousand stars. Together, they form a slightly flattened ball that spans about 160 light-years.
Most of the stars in M5 formed at about the same time, from a single giant cloud of gas and dust. Those stars are about 12 billion years old, and perhaps older.
Almost all of its stars are fainter and less massive than the Sun. Only a few are more impressive — stars that are in the final stages of life, or that’ve been “rejuvenated” by encounters with other stars. Any stars that were born heavier than the cluster’s current population have either exploded or shed their outer layers to expose their hot, dead cores — the remnants of some of M5’s most ancient stars.
Script by Damond Benningfield